On this page you find my experimental build of HMailServer, basically this build has brought forward many of the 5.7 fixes ('issues') into the latest 5.6.x builds for people to use.
It also includes some new scripting eventhandler features as: OnHELO and OnClientLogon and some issues I experienced with SpamAssassin missing the Return-Path headers and a Office 2016 read receipt without From header.